Semiconductor devices which generate large amounts of heat during operations, as semiconductor power modules, employ heat sinks for releasing heat generated from heat producing components, such as IBGTs. In general, a heat sink is constituted by a plate-shaped base on which a heat producing component is placed and a plurality of fins mounted to the base. The fins are placed within a refrigerant flow path, so that heat generated from the heat producing component is transferred to the refrigerant through the base and the fins.
As an example of such a heat sink, Patent document 1 discloses a heat sink having fins made of a porous material so that a refrigerant is flowed through a plurality of holes penetrated through the fins.
Patent document 1: JP 2001-358270, A